A Jackup system is widely used in offshore exploration for drilling wells and gas/oil production. With the increase of demand of energy, the offshore exploration is moving more and more toward the locations where sea ice or other hazards are present. Therefore, the operability range of a Jackup system is critical for its performance.
The existing options for offshore exploration using current Jackup systems include:
1. Drilling exploration wells from a “normal” Jackup system during ice free season with the riser unprotected;
2. Drilling production wells through a fixed production facility using a “normal” Jackup system during ice free season; and
3. Drilling from a large dedicated drilling platform or combined drilling and production platform designed to resist ice loads all year round.
However, the limitation of exploration to ice free season is not desirable. In addition, the large dedicated drilling platform or combined drilling and production platform designed to resist ice loads is a permanent structure that cannot be easily removed for reuse when the drilling activity is complete. Furthermore, it may not be economical for exploration drilling where only a small number of wells are drilled at a location.